Beneath sea urchins’ exterior spines, rounded skeletons called tests are jewels of color, texture, and symmetry. There are hundreds of urchin species, and they’re found in every ocean on ...

Among the many elements that make up the Earth’s crust, a select few are extraordinarily rare, existing only in trace amounts or under very specific geological conditions. This video explores the ...

They had unearthed a 4,500-year-old flint blade fragment — a rare Stone Age find — in the Kernmünsterland region, along ...